What is TCP: drop open request from XX.XX.XXX.XXX/35977?

Question

linux

The server is in a 502 error, got into the logs, found this,
where XX.XX.XXX.XXX is the ip of the same server, that is, its own.

Nov  6 02:02:35 sr kernel: [  870.240736] TCP: drop open request from XX.XX.XXX.XXX/35977
Nov  6 02:02:35 sr kernel: [  870.252678] TCP: drop open request from XX.XX.XXX.XXX/35978
Nov  6 02:02:35 sr kernel: [  870.264672] TCP: drop open request from XX.XX.XXX.XXX/35979
Nov  6 02:02:36 sr kernel: [  870.899587] TCP: drop open request from XX.XX.XXX.XXX/36032
Nov  6 02:02:36 sr kernel: [  870.911564] TCP: drop open request from XX.XX.XXX.XXX/36033
Nov  6 02:02:36 sr kernel: [  870.924563] TCP: drop open request from XX.XX.XXX.XXX/36034
Nov  6 02:02:36 sr kernel: [  870.937545] TCP: drop open request from XX.XX.XXX.XXX/36035
Nov  6 02:02:36 sr kernel: [  870.949625] TCP: drop open request from XX.XX.XXX.XXX/36036
Nov  6 02:02:47 sr kernel: [  881.625123] __ratelimit: 52 callbacks suppressed
Nov  6 02:02:47 sr kernel: [  881.625131] TCP: drop open request from XX.XX.XXX.XXX/36936
Nov  6 02:02:47 sr kernel: [  881.637802] TCP: drop open request from XX.XX.XXX.XXX/36937
Nov  6 02:02:47 sr kernel: [  881.649137] TCP: drop open request from XX.XX.XXX.XXX/36938
Nov  6 02:02:47 sr kernel: [  881.660995] TCP: drop open request from XX.XX.XXX.XXX/36939
Nov  6 02:02:47 sr kernel: [  881.673135] TCP: drop open request from XX.XX.XXX.XXX/36940

Answer 1

maybe SYN floods
triggered the tcp_max_syn_backlog limit